An arrangement in which when the situation is normal a latched state of a door is released by pushing with a small amount of travel an open button provided on the door so as to actuate an electric actuator, and when the latched state of the door cannot be released electrically due to a malfunction caused by a flat battery, etc., an emergency operation is carried out by pushing the open button further than that for normal operation to thus input a mechanical latch release operating force to a latch mechanism via an arm and cable linked to the open button to thereby enable the latched state of the door to be released is known from Patent Document 1.